The dents at top will come out easy with a junk/spare seatpost that is same diameter as original, likely will scratch up the seatpost however so dont use a nice one. If the dents are still noticeable with the seatpost inserted past them, carefully use a plastic or wooden mallet to tap around the outside of dent in order to pop the low center back out.
For the lower set, probably best to make up a special tool consisting of a 2" short section of seatpost size tubing attached to a much longer and slightly smaller diameter tube and attach a slidehammer to top of the tube if needed to withdraw.
If you tried using a 3' long section fo strait seatpost size tubing to reach the lower dents, it would probably get very stuck.

Water bottle bosses would complicate removal of the lower dents but it looks like this frame has none.